Synthesis method for 1-methyl-1H-indazole-6-carboxylic acid
US12258318B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 3, 2020 |
| Grant date | Mar 25, 2025 |
| Priority date | — |
| Expiry date | May 22, 2042 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D231/56
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present application provides a synthesis method for 1-methyl-1H-indazole-6-carboxylic acid. The synthesis method comprises: using 2-fluoro-4-bromobenzaldehyde and methylhydrazine as raw materials to obtain 6-bromo-1-methylindazole by means of an annulation reaction, and then performing a methyl formate reaction and a hydrolysis reaction, so as to obtain the 1-methyl-1H-indazole-6-carboxylic acid. The synthesis method provided in the present application can directly synthesize a 1-position methyl substituted indazole without isomers, thereby avoiding the problem that impurities are difficult to be removed in subsequent separation, thus improving the purity of a product. The yield of the annulation reaction can reach 85%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.